Procedure for a directed hydraulic fill

ABSTRACT

A slurry obtained from a hydraulic excavating or dredging process is passed through classifiers which grade its solid phase according to particle size. The area to be filled is subdivided into a plurality of basins and secondary slurries carrying the fractions are deposited successively in these basins. Simultaneous with the deposition of the coarse-fraction slurry in a second basin and after the settling of the coarse fraction in the first basin, a medium-fraction slurry is deposited in the first basin. Thereafter the coarse-fraction slurry is deposited in a third basin, the medium-fraction slurry in the second basin, and a fine-fraction slurry in the first basin, making a threeblanket-coarse, medium, and fine-layering in the first basin. Then all three slurries are simultaneously deposited and settled down the line in the other basins.

United States Patent m1 Veces'lav 5] Mar. 27, 1973 PROCEDURE FOR A DIRECTED HYDRAULIC Primary Examiner-Robert E. Bagwill [75] Inventor: Harnai D. Veceslav, Bucharest, Atmmey Karl Ross Roman 57 ABSTRACT [73] Asslgnee: x De Pam], Bucharest A slurry obtained from a hydraulic excavating or dredging process is passed through classifiers which [22] Filed: Nov. 3, 1970 grade its solid phase according to particle size. The [2]] Appl- No; 86,484 area to be filled is subdivided into a plurality of basins l and secondary slurnes carrying the fract1ons are deposited successively in these basins. Simultaneous [52] US. Cl. ..47/58, 299/7, 209/44 with the deposition of the coarse-fraction slurry in a [5 Int. Cl. Second and after the ettling of the oarse frag- [58] Field of Search 99/ 209/ tion in the first basin, a medium-fraction slurry is 11 1, 1 deposited in the first basin. Thereafter the coarse-fraction slurry is deposited in a third basin, the medium- 6] References Cited fraction slurry in the second basin, and a fine-fraction slurry in the first basin, making a three-blanket-coarsm' UNITED STATES PATENTS medium, and fine-layering in the first basin. Then all 1,935,638 11/1933 Keese ..209/44 three slurries are simultaneously deposited and settled 1,996,771 4/1935 Macready.; ..299/7 down the line in the other basins, 1,261,198 4/1918 Week et al. .299]? 1,366,456 1 1921 Highfield ..299 x y '8 Claims, 4 Drawing Figures PROCEDURE FOR A DIRECTED HYDRAULIC FILL This invention relates to a procedure for carrying out hydraulic fills to obtain extensive platforms of given profile and bedding.

There are methods of hydraulic embankment using direct deposition'of a slurry in the area to be filled, resulting in a heterogeneous deposit due to the heterogeneous nature of the deposited solid material, to the position of the unloading points in the basins, and to the hydraulic parameters of the slurry. There are also semihydraulic and puddled filling methods in which the transportation or even the deposition does not take place under water, the hydraulic procedures only being used to improve the mixture and to provide as compact a deposit as possible. The directed deposits known are those of limited width such as dams and barrages, where the heterogeneity is caused only by the hydraulic fractionation transverse to the deposit axis.

The present invention eliminates these drawbacks by hydraulically transporting the slurry in a transport networkin which hydraulic classifiers are provided. The

deposition of the fractions occurs in several submerged basins simultaneously but in different time-spaced stages so that the sequence of the stages should provide the necessary bedding or settling time for the fill. All of the fractions are used, to eliminate granulo-metric discontinuities between stages with the slurry of either the coarsest or finest fraction poured first, and in the next strate the desired blankets of intermediate sorts are successively deposited.

According to the invention the hydraulic-fill procedure can be applied to the hydraulic fertilization of sands. For this purpose the suspended colloidal materials are poured into submerged basins where they settle to form a shallow fertile stratum, fertilizing at the same time the inferior sand strate also, because the colloidal materials penetrate into and fill the voids in the sand due to the flow caused by the hydrostatic pressure .in the basin.

An example of the invention is given below, with reference to the drawing in which FIG. 1 is a general diagram of the application of the procedure for directed hydraulic fill with three strata;

FIG. 2 is a section along line 11-11 of FIG. I; and

FIGS. 3A and- 3 are charts illustrating principles of the present invention.

According to this invention the dislocation of the material is made by hydraulic procedures such as suction dredgers A, hydro aspirators B, hydraulic elevators C, or simple mud pumps, according to the material displaced, the topographic location of the deposit as well as of the material storage depot and the equipment available. The primary slurry obtained in this way is pumped to the hydrotransport network in which hydraulic classifiers are provided to sepalrate the solid fractions by desired groups and in given concentrations. The secondary slurries sorted in this way are hydraulically transported by adequate pipes 2 to the submerged deposit basins D1....Dn. Each basin should be provided with drain holes according to the degree of homogeneity and the desired slope of the deposit. The less the slope of the deposit, the greater the number of the unloading points. This number increases directly proportionally to the heterogeneity of the material in the mixture. The two to four groups of fractions resulting from the hydraulic classification of the primary slurry are simultaneously deposited under the form of respective secondary slurries in difierent deposits, according to the granule size desired in each deposit. Due to the filtration of the superior material into the previously poured stream under the action of the hydrostatic charge, no granulomet'ric discontinuities between strate occur.

If it is necessary to obtain in the same deposit successive strate of descending granulometry, starting from the inferior stratum, several basins should be provided so that while the first stratum of high granule size for example for. draining or for providing erosion resistance, is settling in one basin, in the other basin a finer material of the next finer group is settled overthe. stratum of rough material already settled during the previous stage. The third pipe with even finer material should be unloaded in the third group of basins where during the previous stage material of medium grain size has already settled.

To obtain a three strata fill (FIG. 1) the procedure is as follows: (see charts of FIGS. 3A and 38) during the first stage rough material is poured inthe deposit basin DI, the other two groups of finer material are deposited in a dirt-heap or are hydraulically transported toa storage depot; in the next stage this coarse material is lodged in the deposit D2, the medium-grain size material in the deposit D1, and the fine in the quarry or dirt heap; in the last stage the rough material is deposited in the deposit D3, the medium in the deposit D3, the medium in the deposit D2 and the fine in D1. This sequence is repeated down the line until in the last normal stage the rough material is deposited in Dn. During the next stages only the rough material is thrown into the dirt heap or storage depot or this material together with the medium grain size one.

Colloidal and ultra-fine materials of the mixture can serve according to their content for the fertilization and fixing of the superior stratum.

This is obtained by the quiet settling of fine fractions in basins where, during the previous stages, sorted material was'poured. By this fertilization a deep enough stratum of fertile material is obtained. The clogging of the sand voids and the deep penetration of water by infiltration,-together with colloidal fractions, provide a decreasing concentration of fertile particles in the sand. Thus, shallow-rooted vegetation will find nutritive elements not only in the shallow surface stratum, as with the method of dry fertilization, but also in the inferior strate of course in decreasing concentration.

The present invention has the following advantages:

One can obtain well compacted and resistant deposits capable of supporting the significant loads of some buildings built on foundation plate and even on isolated foundations, the strate having a granulometric continuity;

The hydraulic fractional in successive strata provides the draining of inferior strata and a sufficient continuity between strata, forming a unique compact whole not subject to subsequent settling. Deposits with controlled fraction for an effective sanitation of unsanitory areas can be made. A shallow fastening of settled sands and a deep enough decreasing concentration of'the fertilizing colloidal fine material depending on the hydrostatic charge and depth of the settling basin is possible.

SUMMARY Much lower costs than with mechanical procedures are realized, savings were recorded of between 30 and 65 percent as against the cost of the same work done with the usual fill procedures.

Simple equipment is usable for great production capacity on limited zones.

Embankments of much higher quality than the mechanical or homogeneous hydraulic embankments are formed.

Less labor force is required, the daily productivity being up to 400 cu.m/man/day.

The large applicability range allows for stable embankments to be secured, with adequately established profiles depending upon the purpose, and the cost price is competitive with any of the mechanical procedures when used for the same purpose.

Below are a few examples meant to illustrate the manfold applicability of the invention:

1. Draining of an insalubrious zone, for making it adequate for industrial purposes or for town building;

2. Draining operation in any zone;

3. Embankment for building platforms, harbour platforms, shunting stations, highway beds, run-ways, etc;

4. Industrial platforms in zones liable to flooding;

5. Fertile embankments in mine cuts using the thermopower station ash;

6. Hydraulic fertilization of sterile sands;

7. Improvement of beach sand, and arrangement of man-made beaches with sorted submarine sand;

8. Useful embankments made with the alluvion from storage lakes or from submarine deposits.

I claim:

l. A hydraulic-fill process comprising the steps of:

grading the solid phase of a primary slurry by size into a plurality of fractions each with a particle size range different from the others hydraulically transporting said fractions separately but in parallel in respective secondary slurries of different particle-size ranges to a plurality of separated delineated basins; depositing after grading and hydraulic transportation one of said secondary slurries in one of said basins without simultaneously depositing other secondary slurries therein and settling solids therefrom to form a first blanket therein;

subsequently depositing another of said secondary slurries in said one basin while simultaneously depositing said one of said secondary slurries in another basin and settling out the respective particle-size fractions of said solids to form a secondary blanket over said first blanket in said one basin and another first blanket in said other basin; and

repeating the steps of deposition and settling in further basins successively using further fractioncarrying secondary slurries to form in each of said basins a bed of such superposed blankets.

2. The process defined in claim 1 wherein said solid phase is graded into a coarse fraction, a medium-grade fraction, and a fine fraction, said one of said fractions being said coarse fraction and said deposition of subsequent fractions being carried out in order of decreasing particle size.

3. The process defined in claim 2 wherein substantially all of the solid phase of said primary slurry is graded and de osited suchv that no granulometric iscontunity be ween ad acent blankets of each bed results.

4. A method of upgrading a poor-land region comprising the steps of:

hydraulically removing the surface strata of at least a portion of said region, thereby forming a primary slurry with the solid material constituting said strata;

size-grading the solid phase of said primary slurry into at least one coarse fraction, one intermediate fraction, and one colloidally fine fraction;

subdividing a portion of said region into at least three basins; hydraulically transporting said fractions in respective secondary slurries to said basins;

depositing the coarse-fraction slurry in a first of said basin and settling the coarse fraction out to form a coarse blanket therein;

depositing the intermediate-fraction slurry in said first basin and settling the medium fraction out to form an intermediate blanket in said first basin over said coarse blanket while simultaneously depositing and settling the coarse fraction in the second basin to form a respective coarse blanket therein;

depositing the fine slurry in the first basin while simultaneously depositing the intermediate fraction in the second basin and the coarse-fraction slurry in the third basin; and repeating the depositing and settling steps to form a bed in each basin having interstices at least in upper positions filled with the colloidally fine fraction.

5. The method defined in claim 4 wherein the respective slurries are subjected to settling in submerged basins.

6. The method defined in claim 5 wherein said region is subdivided into a matrix of such basins and said basins are blanketed in with the solids of the respective slurries in groups of a number corresponding to the number of particle-size fractions into which said primary slurry is graded.

7. The defined in claim 6 wherein each particle-size range has an upper and a lower limit, the lower limit of 

1. A hydraulic-fill process comprising the steps of: grading the solid phase of a primary slurry by size into a plurality of fractions each with a particle size range different from the others ; hydraulically transporting said fractions separately but in parallel in respective secondary slurries of different particle-size ranges to a plurality of separated delineated basins; depositing after grading and hydraulic transportation one of said secondary slurries in one of said basins without simultaneously depositing other secondary slurries therein and settling solids therefrom to form a first blanket therein; subsequently depositing another of said secondary slurries in said one basin while simultaneously depositing said one of said secondary slurries in another basin and settling out the respective particle-size fractions of said solids to form a secondary blanket over said first blanket in said one basin and another first blanket in said other basin; and repeating the steps of deposition and settling in further basins successively using further fraction-carrying secondary slurries to form in each of said basins a bed of such superposed blankets.
 2. The process defined in claim 1 wherein said solid phase is graded into a coarse fraction, a medium-grade fraction, and a fine fraction, said one of said fractions being said coarse fraction and said deposition of subsequent fractions being carried out in order of decreasing particle size.
 3. The process defined in claim 2 wherein substantially all of the solid phase of said primary slurry is graded and deposited such that no granulometric discontunity between adjacent blankets of each bed results.
 4. A method of upgrading a poor-land region comprising the steps of: hydraulically removing the surface strata of at least a portion of said region, thereby forming a primary slurry with the solid material constituting said strata; size-grading the solid phase of said primary slurry into at least one coarse fraction, one intermediate fraction, and one colloidally fine fraction; subdividing a portion of said region into at least three basins; hydraulically transporting said fractions in respective secondary slurries to said basins; depositing the coarse-fraction slurry in a first of saiD basin and settling the coarse fraction out to form a coarse blanket therein; depositing the intermediate-fraction slurry in said first basin and settling the medium fraction out to form an intermediate blanket in said first basin over said coarse blanket while simultaneously depositing and settling the coarse fraction in the second basin to form a respective coarse blanket therein; depositing the fine slurry in the first basin while simultaneously depositing the intermediate fraction in the second basin and the coarse-fraction slurry in the third basin; and repeating the depositing and settling steps to form a bed in each basin having interstices at least in upper positions filled with the colloidally fine fraction.
 5. The method defined in claim 4 wherein the respective slurries are subjected to settling in submerged basins.
 6. The method defined in claim 5 wherein said region is subdivided into a matrix of such basins and said basins are blanketed in with the solids of the respective slurries in groups of a number corresponding to the number of particle-size fractions into which said primary slurry is graded.
 7. The defined in claim 6 wherein each particle-size range has an upper and a lower limit, the lower limit of a larger one of said ranges coinciding with the upper limit of a smaller one of said ranges, whereby each bed is free from granulometric discontinuities.
 8. The method defined in claim 7 wherein said region is an agricultural plot, further comprising the step of planting the surface of each of said beds after the application of the colloidally fine fraction thereto. 